JEEP WRANGLER 2007 JK / 3.G Owners Manual

Tire pressures change by approximately 1 psi (7 kPa) per
12° F (7° C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage especially in
the winter.
Example: If garage temperature = 68° F (20° C) and the
outside temperature = 32° F (0° C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12° F (7° C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at highspeeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under load is
dangerous. The added strain on your tires could
cause them to fail. You could have a serious accident.
Don’t drive a vehicle loaded to maximum capacity at
continuous speeds above 75 mph (120 km/h).
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Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized dealer for radial tire repairs.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
WARNING!
Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure some-
one. Do not spin your vehicle’s wheels faster than 35
mph (55 km/h) when you are stuck, and do not let
anyone near a spinning wheel no matter what the
speed.
Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.
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These indicators are molded into the bottom of the tread
grooves and will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the indicators appear
in 2 or more adjacent grooves, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.
Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and spare tire should be replaced after six years,
regardless of the remaining tread. Failure to follow
this warning can result in sudden tire failure. You
could lose control and have an accident resulting in
serious injury or death.
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Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
WARNING!
•Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspension
dimensions and performance characteristics, result-
ing in changes to steering, handling, and braking of
your vehicle. This can cause unpredictable handling
and stress to steering and suspension components.
You could lose control and have an accident resulting
in serious injury or death. Use only the tire and wheel
sizes with load ratings approved for your vehicle.
•Never use a tire with a smaller load index or capacity,
other than what was originally equipped on your
vehicle. Using a tire with a smaller load index could
result in tire overloading and failure. You could lose
control and have an accident.
•Failure to equip your vehicle with tires having ad-
equate speed capability can result in sudden tire
failure and loss of vehicle control.
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CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer
readings.
Alignment and Balance
Poor suspension alignment may result in:
•Fast tire wear.
•Uneven tire wear, such as feathering and one-sided
wear.
•Vehicle pull to right or left.
Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your autho-
rized dealer for proper diagnosis.Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
TIRE CHAINS
Install chains on rear tires only. Tire chains may be
installed on all models except the Sahara and Rubicon.
Follow these recommendations to guard against damage
and excessive tire and chain wear:
•Use chains on P225/75R16 tires only. P245/75R16,
P255/75R17, P255/70R18, and LT255/75R17 tires do
not provide adequate clearance.
•Use SAE class “S” tire chains or traction devices only.
•Chains must be the proper size for the vehicle, as
recommended by the chain manufacturer.
•Follow tire chain manufacturer’s instructions for
mounting chains.
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•Install chains snugly and tighten after.6 mile (1 km) of
driving.
•Do notexceed 30 mph (48 km/h).
•Drive cautiously, avoiding large bumps, potholes and
extreme driving maneuvers.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
The suggested rotation method is the “forward-cross”
shown in the following diagram.
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TIRE PRESSURE MONITOR SYSTEM (TPMS) — IF
EQUIPPED
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold placard pressure.
The tire pressure will vary with temperature by about 1
psi (6.9 kPa) for every 12°F (6.5°C). This means that when
the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after a vehicle has not been driven for more than
3 hours - and in outside ambient temperature. Refer to
the “Tires — General Information” in this section for
information on how to properly inflate the vehicle’s tires.
The tire pressure will also increase as the vehicle is
driven, this is normal and there should be no adjustment
for this increased pressure.The TPM System will warn the driver of a low tire
pressure if the tire pressure falls below the low pressure
warning threshold for any reason, including low tem-
perature effects.
The TPM System will continue to warn the driver of low
tire pressure as long as the condition exists, and will not
turn off until the tire pressure is at or above recom-
mended cold placard pressure. Once the low tire pressure
warning has been illuminated, the tire pressure must be
increased to the recommended cold placard pressure in
order for the “Tire Pressure Monitoring Telltale Light” to
be turned off. The system will automatically update and
the “Tire Pressure Monitoring Telltale Light” will extin-
guish once the updated tire pressures have been received.
The vehicle may need to be driven for up to 10 minutes
above 15 mph (25 km/h) to receive this information.
For example, your vehicle may have a recommended
cold (parked for more than 3 hours) air pressure of 35 psi
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(241 kPa). If the ambient temperature is 65°F (18°C) and
the measured tire pressure is 30 psi (207 kPa), a tempera-
ture drop to 20°F (-7°C) will decrease the tire pressure to
approximately 26 psi (179 kPa). This tire pressure is
sufficiently low enough to turn ON the “Tire Pressure
Monitoring Telltale Light.” Driving the vehicle may cause
the tire pressure to rise to approximately 30 psi (207 kPa),
but the “Tire Pressure Monitoring Telltale Light” will still
be ON. In this situation, the “Tire Pressure Monitoring
Telltale Light” will turn OFF only after the tires have been
inflated to the vehicle’s recommended cold placard pres-
sure value.
Base System — If Equipped
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.NOTE:It is particularly important, for you to check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.
The Tire Pressure Monitor System (TPMS) consists of the
following components:
•Receiver Module
•4 Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly. The matching full size
spare tire can be used in place of any of the four road
tires.
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The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster, and an au-
dible chime will be activated when one or more of
the four active road tire pressures are low. The audible
chime will sound once every ignition cycle for each
condition that it detects. Should this occur, you should
stop as soon as possible, check the inflation pressure of
each tire on your vehicle, and inflate each tire to the
pressure recommended by the vehicle manufacturer. The
system will automatically update and the “Tire Pressure
Monitoring Telltale Light” will extinguish once the up-
dated tire pressures have been received. The vehicle may
need to be driven for up to 10 minutes above 15 mph (25
km/h) to receive this information. A low spare tire will
not cause the “Tire Pressure Monitoring Telltale Light” to
illuminate or the chime to sound.The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 60 seconds, and an audible chime will
sound when a system fault is detected. The flash cycle
will repeat every ten minutes, without an audible chime,
until the fault condition no longer exists. If the ignition
key is cycled, this sequence will repeat, providing the
system fault still exists.
NOTE:In the event that the matching full size spare tire
is swapped with a low pressure road tire, the next
ignition key cycle will still show the “Tire Pressure
Monitoring Telltale Light” to be ON, and a chime to
sound. Driving the vehicle for up to 10 minutes above 15
mph (25 kph) will turn OFF the “Tire Pressure Monitor-
ing Telltale Light” as long as the spare tire or any other
road tire(s) are not below the low pressure warning
threshold.
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CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure always
reinstall the valve stem cap. This will prevent mois-
ture and dirt from entering the valve stem, which
could damage the wheel rim sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
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